Dyeing of polyester fibers



United States Patent 3,240,551 DYEING 0F POLYESTER FIBERS Joseph William Fitzpatrick, Pine Beach, and Karl Heinz Lohmann and Oliver Grosz, Toms River, N.J., assignors to Toms River Chemical Corporation, Toms River, N.J., a corporation of Delaware No Drawing. Filed Sept. 27, 1963, Ser. No. 311,959 10 Claims. (Cl. 839) This invention relates to the production of valuable dyeings on fibrous materials of aromatic polyesters, and more particularly to dyed polyethylene terephthalate fibers of excellent color strength and good fastness properties.

Polyester fibers present particular dyeing problems, arising at least in part out of the hydrophobic nature of such fibers. In the dyeing of polyester fibers, the class of dyes known as disperse dyestuffs has come to have the widest application. These dyestuffs are essentially waterinsoluble products applied in a finely divided condition from a dispersion. In the application of such dyestuffs, the dyeing difficulties associated with polyester fibers have been met by the development of special methods for the application of disperse dyes to the fibers. Of these methods, the one known as the Pad/Thermofix method has become of increasing importance since it is particularly adapted for high-speed, continuous dyeing operations. In this method, a fabric is padded by passing it through an aqueous suspension of the dyestuff and squeezing the fabric between closely-set rollers in order to remove excess dye liquor. The dyestuif is only loosely attached to the fiber at this point. The dyestuff is then fixed on the fiber by subjecting the material to a short, intensive heattreatment at elevated temperatures of the order of about 120220 C. It is evident that a dyestuif, in order to be suitable for application by this method, must be fast to sublimation or else it will wholly or partially volatilize from the fiber during the heat-treatment step. The result of such sublimation will be a loss of color value on the polyester fiber and, if a union dyeing operation is being carried out, the staining of the other fibers, such as cotton, which may be present in the blend.

In accordance with the present invention, it has been found that valuable dyeings and prints are produced on fibrous materials of aromatic polyesters, especially polyethylene terephthalate by using as dyestuif a p-toluenesulfonamidoanthraquinone compound from the group consisting of 1-amino-2-methyl-4-p-toluene-sulfonamidoanthraquinone, l-benzamido 4 p toluene-sulfonamidoanthraquinone, l-benzamido 5 p toluene-sulfonamidoanthraquinone, 1 hydroxy-3-methyl-4-p-toluene-sulfonamidoanthraquinone, 1,5-bis p toluene-sulfonamidoanthraquinone and 1,4-bis-p-toluene-sulfonamidoanthraquinone. Instead of the single dyestuffs there can be used a mixture of two of the dyestuffs or a mixture of such a dyestufif with a dyestuif of similar structure.

For dyeing, the said dyestuffs are preferably used in a finely divided form and the dyeing is carried out in the presence of a dispersing agent, such as sulfite cellulose waste liquor or a synthetic detergent, or a combination of different wetting and dispersing agents. Before dyeing, it is generally of advantage to convert the dyestuff or dyestuffs to be used into a dyestuif preparation which contains a dispersing agent and the finely divided dyestuff (s) in such a form as to yield a fine dispersion when the preparation is diluted with Water. Dyestuif preparations of this kind can be made by known methods, for example, by grinding the dyestutf(s) either in dry or wet form with or without the addition of a dispersing agent.

The dyestuffs used in the invention are especially suitable for dyeing by the so-called thermofixation or Pad/- Thermofix method, in which the fabric to be dyed is 3,240,551 Patented Mar. 15, 1966 impregnated advantageously at a temperature not exceed ing 60 C. with an aqueous dispersion of the dyestufi, which may contain 1 to 50% of urea and a thickening agent, especially sodium alginate, and the fabric is squeezed in the usual manner. The squeezing is preferably carried out so that the goods retain 50 to of their weight of dye liquor.

The dyestuif is fixed by subjecting the impregnated fabric to a heat treatment at temperatures above 100 C., for example, at a temperature ranging from -220 C., it being of advantage to dry the fabric prior to this treatment, for example, in a current of warm air.

The thermofixation mentioned above is of special interest for the dyeing of mixed fabrics of polyester fibers and cellulose fibers, especially cotton. In this case, in addition to the dyestuff to be used in the process of the invention, the padding liquor contains a dyestuff suitable for dyeing cotton, for example, a direct dyestuff or vat dyestufi, or more especially a so-called reactive dyestuff, i.e. a dyestuff capable of being fixed on cellulose fibers with the formation of a chemical bond, for example, a dyestuif containing a chlorotriazine or chlorodiazine residue. In the latter case it is of advantage to add to the padding liquor an agent capable of binding acid, for example, an alkali carbonate, alkali phosphate, alkali borate or alkali perborate, or a mixture of two or more of these agents. When vat dyestuffs are used, the padded fabric must be treated, after the heat treatment, with an aqueous alkaline solution of a reducing agent of the kind used in vat dyeing.

The dyeings produced on polyester fibers by the process of the invention are advantageously given an after-treatment, for example, by heating them with an aqueous solution of a non-ionic detergent.

Instead of applying the dyestuffs in the process by impregnation, they may be applied by printing. For this purpose, a printing color is used which, in addition to the usual printing assistants, such as Wetting and thickening agents, contains the finely dispersed dyestutf, if desired, in admixture with one of the aforesaid cotton dyestuffs, and, if desired, in the presence of urea and/ or an agent capable of binding acid.

There are obtained by the practice of the present invention strong dyeings or prints having excellent fastness properties, especially a good fastness to sublimation and to light. Furthermore, the shade and color build-up of the applied dye are outstanding.

The term polyester defines synthetic polymeric polyesters, such as the highly polymeric linear polyesters, the molecules of which have recurring monomeric units connected by ester linkages. Dibasic acids, for example, aromatic acids, such as terephthalic acid, diphenyl-4,4' dicarboxylic acid and/ or dephe-nylsulfone-4,4'-dicarboxylic acid and dihydroxy compounds, for example, glycols, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and/or butylene glycol, as well as other diols, such as 1,4-cyclohexyldiol can be used as the monomers to form the polymeric polyesters. Typical commercial examples of such fibers are Dacron, Terylene, Fortrel, T revira, Terlanca, Kodel, Vycron, etc. They are disclosed, for example, in US. Patent No. 2,901,466 and British Patents Nos. 578,079; 579,462; 588,411; 588,497 and 596,688.

The present invention is, of course, equally applicable to the dyeing of blends of polyester fibers and cellulosic fibers. The latter term includes native cellulose, such as linen or, more particularly, cotton, as well as regenerated cellulose, such as viscose or cuprammonium rayon.

The following examples illustrate the invention, the parts and percentages being by weight.

Example 1 parts of 1-amino-2-methyl-4-p-oluene-sulfonamidoanthraquinone are brought to a state of fine dispersion by ball milling in a ball mill with 2.5 parts of the condensation product of naphthalene-Z-sulfonic acid with formaldehyde, 7.5 parts of sorbitol (other polyalcohols can also be employed) and 50 parts of water An amount of this preparation sufficient to provide a concentration of 3 grams of dyestutr' per liter of dye bath is finely dispersed in Water containing 0.5 g. of sodium alginate per liter and the resultant pad liquor is brought to a temperature of C.

Polyethylene terephthalate fabric is then padded with the above liquor and mechanically squeezed to a 65% pick up. The padded material is then air-dried and developed by dry heat curing in an electrically-heated hotair drier for 1 minute at 200 C. The dyed fabric is scoured for 5 minutes at the boil in a solution containing 3% of sodium di-iso-butylnaphthalene rnonosulfonate and 5% sodium carbonate and then dried. A bluish-red dyeing is obtained, characterized by good penetration and excellent fastness to light and sublimation.

Example 2 The procedure of Example 1 is repeated except that 1- benzamido-4-p-toluene-sulfonamidoanthraquinone is employed in place of 1-amino-2-methyl-4-p-toluene-sulfonamidoanthraquinone. An orange dyeing is obtained, characterized by good penetration and excellent fastness to light and sublimation.

Example 3 The procedure of Example 1 is repeated except that 1- benzamido-S-p-toluene-sulfonamidoanthraquinone is emloyed in place of 1-amino-Z-methyl-4-p-toluene-sulfonamidoanthraquinone. A yellow dyeing is obtained, characterized by good penetration and excellent fastness to light and sublimation.

Exam le 4 The procedure of Example 1 is repeated except that 1- hydroxy 3 methyl 4-p-toluene-sultonamidoanthraquinone is employed in place of 1-amino-2-methyl-4-p-toluene-sulfonamidoanthraquinone. A yellow dyeing is obtained, characterized by good penetration and excellent fastness to light and sublimation.

Example 5 The procedure of Example 1 is repeated except that 1- S-bis-p-toluenesulfonamidoanthraquinone is employed in place of 1-amino-2-methyl-4-p-toluene-sulfonamidoanthraquinone. A yellow dyeing is obtained, characterized by good penetration and excellent fastness to light and sublimation.

Example 6 The procedure of Example 1 is repeated except that 1- 4-bis-p-toluenesulfonamidoanthraquinone is employed in place of 1 amino- 2-rnethyl-4-p-toluene-sulfonamidoanthraquinone. An orange dyeing is obtained, characterized by good penetration and excellent fastness to light and sublimation.

What is claimed is:

1. Polyester fiber dyed with a compound selected from the group consisting of 1-amino-2-methyl-4-p-toluene-sulfonamidoanthraquinone, l-benzamido 4 p-toluene-sulfonamidoanthraquinone, 1-benzamido-S-p-toluene-sulfonamidoanthraquinone, 1 hydroxy 3-methyl-4-p-toluenesulfonamidoanthraquinone, 1,5-bis-p-toluene-sulf0namidoanthraquinone and 1,4-bis-p-toluene-sulfonamidoanthraquinone,

2. Polyester fiber according to claim 1, in which the polyester fiber is polyethylene terephthalate.

3. Polyester fiber according to claim 1 in which the compound is 1-amino-2-methyl-4-p-toluene-sulfonamidoanthraquinone.

4. Polyester fiber according to claim 1 in which the compound is 1-benzamido-4-p-toluenc-sulfonamidoanthraquinone.

5. Polyester fiber according to claim 1 in which the compound is 1-benzamido-5-p-toluene-sulfonamidoanthraquinone.

6. Polyester fiber according to claim 1 in which the compound is 1 hydroxy 3 methyl-4-p-toluene-sulfonamidoanthraquinone.

7. Polyester fiber according to claim 1 in which the compound is 1,5-bis-p-toluene-sulfonamidoanthraquinone.

8. Polyester fiber according to claim 1 in which the compound is 1,4-bis-p-toluene-sulfonamidoanthraquinone.

9. A process of dyeing and printing a polyester material, which comprises applying to fibrous material of synthetic polyester an aqueous dispersion containing a compound selected from the group consisting of l-amino- 2-methyl-4-p-toluene-sulfonamidoanthraquinone, 1 benzamido 4 p-toluene-sulfonamidoanthraquinone, l-benzamido 5 p toluene-sulfonamidoanthraquinone, l-hydroxy 3 methyl 4-p-toluene sulfonamidoanthraquinone, 1,5 bis p-toluene sulfonamidoanthraquinone and 1,4-bis-p-toluene-sulfonamidoanthraquinone.

'10. Process according to claim 9, in which the polyester fiber is polyethylene terephthalate.

References Cited by the Examiner UNITED STATES PATENTS 1,928,725 10/1933 Honold et al. 8--39 X 2,394,918 2/1946 Kienle et al. 870 3,084,015 4/1963 Grossman et al. 839 3,087,773 4/1963 Straley et a1. 8--39 3,097,909 7/1963 Rhyner et al. 839 3,164,436 1/ 1965 Altcrmatt 839 NORMAN G. TORCHIN, Primary Examiner.

T. J. HERBERT, Assistant Examiner. 

9. A PROCESS OF DYEING AND PRINTING A POLYESTER MATERIAL, WHICH COMPRISES APPLYING TO FIBROUS MATERIAL OF SYNTHETIC POLYESTER AN AQUEOUS DISPERSION CONTAINING A COMPOUND SELECTED FROM THE GROUP CONSISTING OF 1-AMINO2-METHYL-4-P-TOLUENE-SULFONAMIDOANTHRAQUINONE, 1 - BENZAMIDO - 4 - P-TOLUENE-SULFONAMIDOANTHRAQUINONE, 1-BENZAMIDO - 5 - P - TOLUENE-SULFONAMIDOANTHRAQUINONE, 1-HYDROXY - 3 - METHYL - 4-P-TOLUENE - SULFONAMIDOANTHRAQUINONE, 1,5 - BIS - P-TOLUENE - SULFONAMIDOANTHRAQUINONE AND 1,4-BIS-P-TOLUENE-SULFONAMIDOANTHRAQUINONE. 